Regulation of smooth muscle actomyosin function.
Regulation of smooth muscle actomyosin function.
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平滑肌肌动球蛋白功能的调节。
DOI：
10.1007/978-1-4684-6003-2_4
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发表时间：
1991
影响因子：
--
通讯作者：
S. Maruta
中科院分区：
文献类型：
--
作者：
M. Ikebe;T. Mitsui;S. Maruta
人们普遍认为平滑肌收缩装置主要受肌球蛋白20 kDa轻链可逆磷酸化和去磷酸化调控（Hartshorne, 1987）。负责磷酸化的酶是Ca2+/钙调蛋白依赖性肌球蛋白轻链激酶（MLCK），这是赋予平滑肌收缩器Ca2+敏感性的关键酶（Hartshorne, 1987）。磷酸化假说的另一个关键组成部分是肌球蛋白轻链的去磷酸化，这是由蛋白质磷酸酶催化的。从平滑肌细胞的可溶性部分中纯化了几种蛋白磷酸酶。Pato及其合作者（Pato和Adelstein， 1983a, 1983b； Pato和Kerc， 1985）报道了从砂囊平滑肌可溶性部分中提取的四种蛋白磷酸酶，其中三种（SMP I， II和IV）已被纯化。其中，SMP III和IV能够使完整肌球蛋白去磷酸化。纯化后的SMP-IV分子量为150 kDa，由两个分子量为58 kDa和40 kDa的亚基组成。SMP-IV优先使磷酸化酶激酶α-亚基（已知的1型磷酸酶底物）去磷酸化，但对已知特异性抑制1型磷酸酶的抑制剂-2不敏感。磷酸酶也从主动脉平滑肌的可溶性部分纯化出来（Werth et al., 1982; DiSalvo and Gifford 1983; Erdodi et al., 1989）。Erdodi等人（1989）最近从狗主动脉平滑肌中纯化了两种磷酸酶，它们能使天然肌动球蛋白去磷酸化。260 kDa的磷酸酶的性质与2A型磷酸酶相似。另一方面，一个150 kDa的磷酸酶使磷酸化酶激酶的α-亚基去磷酸化，尽管它不受抑制剂1或抑制剂2的抑制，这是已知的1型蛋白磷酸酶的特异性抑制剂。这些报告表明，从可溶性部分纯化的平滑肌磷酸酶可能与1型和2型磷酸酶不同，这些酶可以使肌球蛋白去磷酸化。然而，这些磷酸酶是否负责体内收缩的调节尚不清楚。此外，磷酸酶活性是否受生理调控尚不清楚，这是有待阐明的最重要领域之一。
It is widely accepted that the smooth muscle contractile apparatus is primarily regulated by reversible phosphorylation and dephosphorylation of the 20 kDa light chain of myosin (Hartshorne, 1987). The enzyme which is responsible for the phosphorylation is the Ca2+/calmodulin dependent myosin light chain kinase (MLCK) and this is the key enzyme to confer Ca2+ sensitivity to the smooth muscle contractile apparatus (Hartshorne, 1987). Another critical component of the phosphorylation hypothesis is the dephosphorylation of the myosin light chain which is catalyzed by a protein phosphatase. Several protein phosphatases have been purified from the soluble fraction of smooth muscle cells. Pato and collaborators (Pato and Adelstein, 1983a, 1983b; Pato and Kerc, 1985) reported four protein phosphatases from gizzard smooth muscle soluble fraction and three of which (SMP I, II and IV) have been purified. Among them, SMP III and IV can dephosphorylate intact myosin. The purified SMP-IV has a molecular weight of 150 kDa and is composed of two subunits of MW 58 kDa and 40 kDa. SMP-IV preferentially dephosphory-lates the α-subunit of Phosphorylase kinase (a known substrate of Type 1 phosphatases) but is insensitive to Inhibitor-2 which is known to inhibit Type 1 phosphatases specifically. Phosphatases have also been purified from the soluble fraction of aortic smooth muscle (Werth et al., 1982; DiSalvo and Gifford 1983; Erdodi et al., 1989). Erdodi et al. (1989) recently purified two types of phosphatases from dog aortic smooth muscle which dephosphorylate native actomyosin. A 260 kDa phosphatase was similar in its properties to the Type 2A phosphatases. On the other hand, a 150 kDa phosphatase dephosphorylated the α-subunit of Phosphorylase kinase although it was not inhibited by Inhibitor 1 or Inhibitor 2, which are known to be specific inhibitors of Type 1 protein phosphatase. These reports suggest that smooth muscle phosphatases purified from the soluble fraction, which dephosphorylate myosin, may be different from both Type 1 and Type 2 phosphatases. However, it is still obscure whether or not these phosphatases are responsible for the regulation of contraction in vivo. Furthermore, it is not known if phosphatase activity is physiologically regulated, and this is one of the most important areas to be elucidated.
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主动脉平滑肌中两种类型的磷酸酶对肌球蛋白轻链中不同位点的去磷酸化。
DOI：
10.1016/0167-4889(89)90080-3
发表时间：
1989
期刊：
Biochimica et biophysica acta
影响因子：
--
作者：
Erdödi,F;Rokolya,A;Bárány,M;Bárány,K
通讯作者：
Bárány,K
平滑肌肌球蛋白荧光标记的 20,000 道尔顿轻链的交换。
影响因子：
2.9
作者：
Morita,J;Takashi,R;Ikebe,M
通讯作者：
Ikebe,M
DOI：
--
发表时间：
1989-12
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
P. Cohen;P. Cohen
通讯作者：
P. Cohen;P. Cohen
平滑肌肌球蛋白的构象依赖性蛋白水解。
DOI：
--
发表时间：
1984
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Ikebe,M;Hartshorne,DJ
通讯作者：
Hartshorne,DJ
扇贝肌原纤维和外来调节轻链之间的杂交形成。
影响因子：
5.6
作者：
Sellers,JR;Chantler,PD;Szent-Györgyi,AG
通讯作者：
Szent-Györgyi,AG